Sara saw the man walking the dog as she was walking home from visiting friends. As they approached from the cross-street, Sara noticed that the man was fairly ordinary, middle-aged, average height, medium build. The dog on the other hand was anything but ordinary. A beautiful rotweiler, obviously male, large for the breed, straining at its leash. Sara couldn't take her eyes off it as the moved toward the intersection.

They reached the intersection at the same time, and man and dog turned to follow the same street Sara was on, both having to wait for a stop light. The rottweiler sidled up to Sara and stuck his snout into the crotch of her shorts, making snuffling noises. Sara giggled, but somewhere back in the the most primitive part of her brain, something dark stirred as she felt the dog's snout press against her crotch.

"Otto, no!" The man pulled back on the rottweiler's leash, and the dog backed off, rejoining his master. "Sorry, he tends to be a little overly friendly sometimes."

"That's okay, I like dogs. And they usually like me, too. He's beautiful. His name's Otto?"

"Yep. And I'm Mike, by the way. You know a lot of people are afraid of rottweilers."

"I'm Sara. I've never been afraid of any kind of dog. I like being around them."

By now they were walking down the street together, toward Sara's house, although it was still several blocks away. The dog kept moving over to nuzzle Sara, and Mike kept pulling him back. Sara noticed that Mike was sneaking peeks at her every chance he got. Sara was used to that. In her early 20s, she was hot, with a beautiful face and a nice body. She knew guys liked to look, especially at her 32DD tits. Most guys never really got past those tits, but Mike seemed to be having a good look at her flat belly and slim hips, too. Of course, she wasn't exactly dressed to cover any of it up, in a skimpy tank top and shorts.

They made small talk as they walked the next block, then Mike said, "This is my place. Have to put Otto in the back yard."

Sara walked with him as he took the dog to the gate into the back and let him through. Sara was turning to head for her house when Mike suddenly grabbed her, pinning her against him, and clamped a hand over her nose and mouth. She struggled against him, but he was much too strong for her. She couldn't cry out, couldn't breathe. She felt herself becoming weaker. Gathering all her remaining strength, she made one last attempt to break free. She failed, then everything went black.

*****Sara awoke, coming to slowly, still groggy. Her nose itched. She tried to scratch it, but couldn't move her hands. She slowly became aware of why her nose itched. She was lying face down on grass. Naked. Her hands were tied together, and tied to a post in the ground. As she tried to move she realized that her ankles were also bound, although they weren't tied together like her wrists. In fact, they were bound so that she couldn't move her legs together. There was something around her neck. It was stiff, like leather, not tight enough to be uncomfortable, just enough to notice that it was there.

"Damn, girl, you have an incredible body!" She recognized the voice. It was Mike. She turned her head and saw him, standing a couple of feet away, naked as she was. She looked around more, saw the fencing around her, the small structure in the corner, and realized where she was. In Otto's kennel in Mike's back yard.

"What... what are you going to do with me? Are you going to rape me?" Sara was still a little woozy from having been unconscious, and was trying to make sense of what was happening.

Mike chuckled. "I'm not going to do anything to you. Yet. But you and Otto were getting along so well that I thought you should get to know each other better." Something in Mike's tone made Sara very nervous. But there was also something about the situation that excited her as few things ever had before.

Sara felt a tug on the band around her neck, and noticed for the first time that Mike was holding something in his left hand. A leash. It slowly dawned on her that what she felt around her neck was a dog collar. Her eyes got wide, and she looked at Mike again. He was grinning, and Sara shivered at the look of him.

"That's right, you've got your own collar now. All of Otto's bitches get collars. In fact, that's what yours says - Bitch. So everyone knows what you are, and you don't forget. Otto! Come here boy!"

The dog walked out of his house and moved toward Sara. Down here, on his level, Otto looked even more muscular. The dark, crouching thing in the back of Sara's brain began to stir again as the dog approached. Otto walked up behind Sara, and again pressed his snout against Sara's crotch. This time, though, there were no shorts between the dog's cold, wet nose and Sara's sensitive skin. She jerked when she felt the touch of Otto's snout. The primitive beast in the back of her brain began to howl. This was her deepest, darkest secret, the thing she'd never admitted even to herself. The thought of being used by a dog was her ultimate sexual fantasy.

Sara felt Otto's tongue begin to lap at her pussy and ass. She began to moan, low, deep in her throat. She shifted her position to get up on all fours; yes, they didn't call it "doggy style" for nothing. As she moved, she saw Mike standing in front of her, stroking his hard cock as he watched what was going on.

Sara's moans were getting louder and more frequent as the dog's tongue lapped at her pussy. Suddenly, she felt him press his muzzle hard against her. His tongue snaked out, slid between her pussy lips, and entered her, reaching up inside.

"Ahhhh, god!" Sara's pussy clamped around the dog's tongue, and her body trembled as she felt him exploring the inside of her pussy. After a minute or so, she felt his tongue pull out, and she whimpered, afraid that he was done with her. But then he felt the dog's front paws scrabbling across her back and shoulders as he lifted himself up onto her. She felt something bumping against her inner thighs and the lips of her pussy. She knew it had to be Otto's doggy cock, and she knew she wanted it, deep inside her, fucking her like the bitch she was. For a brief second, as she felt the dog's cock bang against her, she was afraid he wouldn't be able to enter her.. But then, he thrust forward and for the first time she felt herself being violated by a dog. Her pussy squeezed hard on Otto's cock as he began to hump her, hard and fast. She looked up briefly and saw Mike, still stroking himself as he watched, then closed her eyes and gave herself over to her depravity.

"God, yes, yes! Fuck me like a bitch! Turn me into a bitch!" Her mind now belonged completely to the dark, crouching thing that usually hid from the world. Her body thrashed, out of control. The dog's cock drove into her pussy, penetrating deep into her body. His front paws clawed at her, scratching her back and shoulders, the pain adding to the feelings surging through her body.

Suddenly her mind and body exploded together, spasms racked her, she lost her breath in a single explosion of air. The orgasm was like no other she'd ever experienced, taking in her entire body. Sara felt like she was being turned inside out. She was shaking so bad she could barely breathe, and was afraid she might pass out again.

As Sara's orgasm engulfed her, Otto continued humping her with his dog cock. On one stroke he pulled back too far. His cock slipped out of Sara's pussy. On the return stroke, the dog's cock banged against the flesh that divided Sara pussy from her ass, angled upward, and slid to the hilt into Sara's ass. Sara gasped as she felt her ass take in Otto's dick.

"Ahhh, yes, fuck my ass! God, it's so good!"

Sara was one of those rare women who love being fucked in the ass. Now she was not only living her fantasy of being fucked by a dog, but the dog was reaming her favorite hole. She was in heaven. Otto, oblivious to the difference between Sara's holes, kept humping his cock into Sara's ass as vigorously as he had into her pussy. Having a dog's cock in her ass was the ultimate turn-on for Sara, and her body and mind responded as never before. The thing in the back of her mind was now a shrieking animal, drowning out all else. Suddenly, Otto whimpered and slammed even harder into Sara's ass. She felt his doggy cock twitch, and his cum begin to spurt into her. Feeling the dog's cum filling her ass was enough to trigger another orgasm for Sara. Her body shook as she gasped for breath.

"God, I'm cumming! Yesssss!" Sara moaned as Otto spurted inside her ass. Her body heaved, this orgasm shaking her even more violently than the last. Sara shuddered one last time, then fell forward onto the grass as she felt the dog's cock slip out of her. As Otto crawled away, Sara looked up at Mike, who was still holding her leash.

"Are you ready for me now?" he asked.

Sara moaned. Being fucked by the dog had left her totally spent, her orgasms draining all of her energy. But she wasn't going to get any rest. Mike walked around behind her, to where Otto had been, and pulled up on the leash.

"Get back up, you're not done yet!"

Sara slowly raised herself back up on her hands and knees, and felt Mike's cock probing the lips of her pussy. The head poked inside her, then she felt him slam forward, his cock splitting open her hole.

"Damn, you're a tight bitch!" Mike exclaimed.

"Fuckin' right, I am!" Having a cock inside her had perked Sara up again, and she was feeling like giving as good as she got. And she was really proud of what one of her lovers had once told her - "You're every man's dream. Tight as a virgin and fuck like a porn star."

Mike was driving his cock into her hard, obviously driven to a frenzy by watching his dog fuck the young woman. He reached around her with one hand and began massaging her clit, leaning forward so he was resting on her back almost the same way Otto had. With his other hand he tugged lightly on the leash, causing the collar to bite into Sara's throat slightly; not enough for real pain or to cut off her breath, but enough to cause her mind to check out again as her body and instincts took over completely.

Just as she felt herself getting ready to explode, Mike slowed his thrusts, and moved his hand from her clit, using it to rub her belly instead.

"Damn it, don't stop!" Sara's voice trembled with frustration.

"Oh, don't worry, I'm not going to stop." Mike's cock was still moving inside her, but slowly now, less forcefully. "I just don't want this to be over too soon."

Sara's body relaxed slightly, her breathing slowed as Mike fucked her more gently. He continued the slow, rhythmic strokes for a couple of minutes, then began to pick up the pace again, moving his fingers back to her clit. Sara gasped when he pulled on the leash again, harder than he had before. Sara's body began to build toward orgasm again, her breath coming in short gasps. Her pussy pulsed around Mike's cock, and her clit was throbbing under the touch of his fingers. Then he slowed again.

"NO!!!" Sara screamed. "Fuck me hard! I need it!"

"Just teasing you." Mike sounded like he was almost giggling.

Suddenly he began fucking her with a fury she'd never before experienced. He jerked on the leash, again harder than before, this time bringing actual pain. His cock pounded into her so hard she was afraid something would rip inside her. His fingers pinched and twisted her clit, sending shock after shock through her. Sara began gasping in huge breaths, letting them out in screams.

"YES!!!...HARDER!!! MAKE ME!!!...CUM!!!...AAAAIIIIEEEE!!!!"

Sara thrashed convulsively as Mike buried his cock in her one last time. She felt his cum spurting into her pussy as the strongest orgasm of her life rolled over her, shaking her to her core. Her body vibrated like an electric current was running through it. Then, as Mike began to pull his cock out of her, she squealed, and squirted, spraying Mike's cock and balls, the inside of her own thighs, and the ground under her.

Sara collapsed on the ground again, this time in no condition to move at all. Soft moans escaped her lips as she tried to catch her breath. She couldn't quite get comfortable on the ground with her hands and feet bound.

Sara was barely aware of her surroundings, but she could almost sense the dog, Otto standing nearby, watching her. She vaguely felt Mike untie her hands and feet, and then unhook the leash, although he left the collar on her. She felt herself being scooped up in his arms.

"Let's get you into the house, baby, you look like you could use a rest. Otto, I think we wore her out."